Load-brake mechanism for hoisting or other machines.



No. 75,424. Patented Dec. 9, I902.

' H. SAWYEB.

LOAD BRAKE MECHANISM FOR HOISTING OROTHER MACHINES.

(Application filed Mar. 24. 1902- (,No Model.) 2 Sheets-Sheet l.

1 5-: L I E T 12 r Wk No. 7l5,424. Patented Dec. 9, I902. H. SAWYER.

V LOAD BRAKE MECHANISM FOR HOISTING OR OTHER MACHINES.

(Application filed Mar. 24, 1902.)

2 Sheets-Sheet 2.

Wife-55a s UNITE STATES PATENT OFFICE.

HARRY ,SAlVYER, OF MUSKEGON, MICHIGAN.

LOAD-BRAKE MECHANISM FOR HOISTING OR OTHER MACHINES.

SPECIFICATION formingpart of Letters Patent No. 715,424, dated December 1902- Application filed March 24, 1962. Serial No. 99,604. (No model.)

To all whont it may concern:

Be it known that I, HARRY SAWYER, a citizen of the United States, residing at Muskegon, in the county of Muskegon and State of Michigan, have invented a new and useful Improvement in Load-Brake Mechanism for Hoisting or other Machines, of which the following is a specification.

This invention relates to load-brake mechanism for hoisting or other machines.

The object of the invention is to simplify and improve the construction of mechanism of the class referred to and to render the same more eflicient in operation.

Theinvention consists, substantially, in the construction, combination, location, and arrangement of parts, all as will be more fully hereinafter set forth, as shown in the accompanying drawings, and finally pointed out. in the appended claims.

Referring to the accompanying drawings, and to the various views and reference-signs appearing thereon, Figure 1 isa view in perspective of a load-brake mechanism embodying the principles of my invention, the parts being in assembled relation ready for use. Fig. 2 is a similar view showing the parts separated, so as to disclose the construction of each. Fig. 3 is a view in horizontal section on the line 3 3, Fig. 4, and looking in the direction of the arrows. I Fig. 4 is a View in transverse section on the line 4 4, Fig. 3, looking in the direction of the arrows.

The same part is designated by the same reference-sign wherever it occurs throughout the several views.

In the drawings reference-sign A designates the power or other shaft upon which the brake mechanism is mounted and which may receive rotation from a motor or other convenient source of power. (Not shown.)

Upon shaft A are mounted two oppositelyfaced flanges B O. The flange B is keyed solidly to shaft A, and the inner face of the hub thereof is provided with a spiral camsurface, as clearly shown at D, Figs. 2 and I). The hub E of flange O is loosely sleeved upon shaft A and on the inner face thereof is provided with a spiral cam-surface F, arranged to engage and cooperate with the spiral cam-surface D of flange B, whereby when a rotative effort is imparted to one or ,oted upon a convenient fixed bracket T.

the other of said flanges in proper direction the engagement of said spiral cam-surfaces with each other tend to separate or force apart said flanges. The hub of flange C is adapted to be geared to the load. This may be accomplished in any suitable manner-as, for instance, through a pinion G, mounted on or formed with a sleeve which is keyed to hub E. On the juxtaposed faces of flanges B C are formed heavyinterlocking lugs H J, suitably spaced apart and proportioned to permit a desirable range of relative rotation of said flanges to enable the spiral cam-surfaces D and F to effect the desired separation of the flanges B C, while at the same time preventing an undue relative rotation of said flanges. A cylindrical casing K is arranged to inclose the flanges B and C, said casing being provided with a sleeved end plate M, having a sleeved bearing upon an extended hub portion of flange G, and at its other end said casing is provided with a hub L, sleeved and bearing upon shaft A. The casing K and its end plate M, which is bolted or otherwise connected thereto or constructed to form part thereof, are provided on the inner side walls thereof with frictional bearing-surfaces, with which respectively cooperate similar hearing or friction surfaces N, formed on the flanges B and O, as clearly shown in the drawings. If desired and in order to secure greater friction between these cooperating bearing-surfaces, friction rings or strips 0 P may be interposed therebetween. Mounted on or formed with casing K is a ratchet-ring Q, with which ongages one or more pawls R S, suitably piv- If desired and preferably, the pawls R and S may be arranged to engage behind the teeth of ratchet-ring Q at different intervals. For instance, and as shown in Fig. 4, when pawl R is engaging behind a ratchet-tooth pawl S may occupy a position half-way between adjacent teeth. The pawls R S are each provided with an arm A B. The arm A is arranged to be received in a seat formed in or otherwise engaged by a bracket or casting O, forming part of or to which is connected the ends or a friction band or strap D, arranged to embrace and surround the hub L of the ratchet ring or casing K. The opposite ends of said friction strap or band are connected together by means of a spring E, the tension of which is constantly exerted upon the ends of said strap or band to draw the same into efficient embracing application to the peripheral surface of hub L. In this manner not only is an extended frictional clamping-surface provided, but any wear of such surface is promptly taken up and compensated. Similarly the arm B is arranged to be engaged by or received in a seat formed in a bracket or casting F, to which arm is connected or with which is formed a similar friction band or strap G, arranged alongside of band or strap D and also embracing or surrounding hub L and having its free ends drawn together in embracing relation with respect to said hub by means of a tension-spring H in a manner similar to that above described with reference to band or strap D. Suitable logs or stops J K may be provided to limit the rocking movement of the pawls R S away from engaging position with reference to the ratchet-teeth of ring Q. It will be observed that both pawls R. S engage the teeth of ratchet-ring Q in the same direction, thereby permit-ting casing K to freely rotate in one direction, but preventing rotation thereof in the opposite direction. The brackets or castings C F may, if desired, be provided with pockets L, adapted to receive a lubricant and supply the same in any suitable manner to the bearing-surfaces of hub L and friction bands or rings D G.

The operation of the device will be readily understood from the foregoing description, taken in connection with the accompanying drawings, and is as follows: Rotation is imparted to the shaft A from a motor or other convenient source of power and in a direction permitting the rotation of the ratchetring Q or casing K. The flange 0 being geared to the load through pinion G, it will be seen that the rotation of shaft A will impart a rotative movement of flange B relative to flange O. This relative rotative movement causes the spiral cam-surface D to engage the cooperating cam-surface F on the hub of flange 0, thereby causing flanges B and G to be forced away from each other, and hence pressing the friction-surfaces N of said flanges into frictional contact with the cooperating and juxtaposited surfaces formed on casing K and its end plate M, and hence causing the flange O and its pinion G to be driven positively from flange B and raising the load or per forming such other work as may be required. It will be seen that the initial rotative movement imparted to the shaft A at the beginning of the operation caused or tended to cause the friction bands or straps D G to revolve therewith. This tendency of said bands or straps .to revolve with the shaft and hub L, which, as above explained, is mounted to revolve with shaft A, imparts a rocking motion to arms A B of locking-pawls R S and in a direction to cause said pawls to become disengaged from the ratchet-teeth of ring Q.

The stops J K arrest the rocking movement of said pawls before the arms A B are carried so far as to become disengaged from brackets O F, and consequently the friction bands or straps D G are thereafter held against rotation with shaft A or hub L, and the pawls are held out of contact with the ratchet-teeth of ring Q, and hence avoiding the noise incident to said ratchet-teeth riding over loose pawls. Moreover, the friction bands or straps D G are maintained in frictional engagement with hub L ready to be instantly moved rotatively in the opposite direction should the motor or driving-power be reversed or should a reverse rotative eflort be imposed on shaft A, and such opposite rotative movement of said straps or bands will effect an instant and automatic application of the pawls R S into engaging relation with respect to the ratchet-teeth of ring Q. Thus when the load'has been raised to the desired height or the desired work has been accomplished and the motor is arrested the load will impose a reverse rotative effort upon flange O, which through the spiral cam surfaces D F will force the flanges B C apart and cause the frictional engagement of the bearing-surfaces of said flanges with casing K, and hence impart a rotative effort to casing K and a consequent automatic application of the pawls R and S to ratchet-ring Q, thereby arresting and locking the load against further lowering movement. It will be seen that the lockingpawls are applied automatically and instantaneously to lock the parts against reverse movement and before an undue speed of reverse rotation is imparted to the ratchet-ring, and consequently I avoid the danger of injuring or breaking the pawls or the ratchetteeth. When it is desired to lower the load, the motor is run in the reverse direction from that in hoisting. The first action of this reverse rotation of the driving-motor is to screw the spiral cam-surface D into the spiral camsurface F, and hence relieving partially or Wholly the friction between the flanges B O and easing K, and hence permitting the flange O to rotate in a direction to lower the load. The load, however, cannot run ahead of the motor, for that would result in the application of the friction-surfaces of flanges B C to the cooperating surfaces of casing K through the medium of the spiral cam-surfaces .D F.

By the construction above described it will be seen thatI bring the parts when assembled into close relati0n,thereby enabling the casing K to serve as an inclosing casing for the friction driving-surfaces, thereby excluding dust and dirt therefrom. It will also be seen that by employing an inclosing casing the same may be utilized to contain a lubricant to reduce the Wear as much as possible. It will also be seen that I provide extensive areas of frictional contacting-surfaces. It will also be seen that by mounting the friction-rings D G upon the hub L, I secure an extensive frictional surface for the proper operation of the IIO locking-pawls and that the tension-springs H E efficiently take u p any Wear,and any dust or dirt is excluded from the bearingsurfaces, thereby preventing, undue wear thereon.

It is obvious that many variations and changes in the details of construction and arrangement would readily occur to persons skilled in the art and still fall within the spirit and scope of my invention. I do not desire, therefore, to be limited or restricted to the eX- act details of construct-ion and arrangement set forth; but,

Having now explained the object and nature of my invention and a construction embodying the principles thereof, what I claim as new and useful and of my own invention, and desire to secure by Letters Patent, is-

1. In a load-brake, a shaft adapted to be rotated from any suitable source of power, flanges mounted upon said shaft, one of said flanges mounted to rotate with the shaft and the other loose upon said shaft and geared to the load, engaging spiral surfaces formed on said flanges respectively, whereby a rotative tendency of one of said flanges relatively to the other effects a separation thereof, and bearing-surfaces with which said flanges enga e when separated to lock the same to rotate in unison, all combined and arranged as and for the purpose set forth.

2. In a load-brake mechanism, a rotatable shaft, a radial flange mounted thereon to rotate therewith, a cooperating radial flange loosely sleeved upon said shaft and adapted to be geared to the load, bearing-surfaces with which said flanges respectively cooperate, means whereby relative rotation of said flanges effects a separation of the same to cause said flanges to engage their cooperating bearing-surfaces for frictionally coupling said flanges to support the load when said flanges are separated, as and for the purpose set forth.

3. In a load-brake mechanism, a rotatable shaft, a flange mounted upon said shaft to rotate therewith and provided with aspiral camsurface, a cooperating flange loosely sleeved upon said shaft and provided with a cooperating spiral cam-surface whereby relative rotation of said flanges effects an engagement of said spiral cam surfaces to force said flanges apart, said loosely-sleeved cam being geared to the load, bearing-surfaces with which said flanges respectively cooperate when said flanges are forced apart or separated for frictionally coupling said flanges, all combined and arranged as and for the purpose set forth.

a. In a load-brake mechanism, a rotatable shaft, a radial flange mounted thereon to rotate therewith, said flange provided with a spiral cam-surface and a frictional bearingsurface, a cooperating radial flange loosely sleeved upon said shaft and provided with a cooperating spiral cam-surface and also a frictional bearing surface, said looselysleeved flange being geared to the load whereby a relative rotation of said flanges effects a separation thereof through the engagement of said spiral cam-surfaces with each other, and a casing having radial bearing-surfaces adapted to cooperate with the bearing-s11 rfaces on said flanges when the latter are forced apart, as and for the purpose set forth.

5. In a load-brake mechanism, a rotatable shaft, aradial flange mounted upon said shaft to revolve therewith, a cooperating radial flange loosely sleeved upon said shaft and geared to the load, said flanges provided with cooperating spiral cam-surfaces upon the opposed faces thereof and having frictional bearing-surfaces upon the outer faces thereof, in combination with an inclosing casing for said flanges and having bearing-surfaces with which the bearing-surfaces on the outer faces of said flanges respectively cooperate, whereby when said flanges are forced apart they are coupled together frictionally, as and for the purpose set forth.

6. In a load-brake mechanism, a rotatable shaft, a flange mounted thereon to rotate therewith,a cooperating flange loosely sleeved upon said shaft, means whereby when one of said flanges is revolved relatively to the other they are forced apart or separated, means operated by the separation of said flanges for coupling the same together to revolve in unison, and means for locking said flanges against reverse rotation when so coupled, as and for the purpose set forth.

7. In a load-brake mechanism, a revoluble shaft, a flange mounted thereon to rotate therewith, a flange loosely sleeved upon said shaft and geared to the load, and automatic stop mechanism for positively preventing reverse rotation of one of said flanges, as and for the purpose set forth.

8. In a load-brake mechanism, a revoluble shaft, a flange mounted thereon to rotate therewith, a flange loosely sleeved upon said shaft and geared to the load, said flanges provided with spiral cam-surfaces upon the opposed faces thereof, whereby when one of said flanges is rotated relatively to the other said flanges are forced apart or separated, means for frictionally coupling said flanges when they are forced apart or separated, a lockingratchet for said coupling, a locking-pawl cooperating with said ratchet, and means for automatically applying and releasing said locking-pawl, as and for the purpose set forth.

9. In a load-brake mechanism, a rotatable shaft, a flange mounted thereon to rotate therewith, a cooperating flange loosely sleeved upon said shaft and geared to the load, said flanges provided with interlocking spiralcamsurfaces upon the opposed faces thereof, whereby a relative rotation of said flanges causes said flanges to be separated or forced apart, means for frictionally coupling said flanges when forced apart,a ratchet-ring, a pivotally-mounted pawl cooperating with said ratchet, and a friction-strap operating to automatically apply and release said pawl, as and for the purpose set forth.

10. In a load-brake mechanism, a rotatable shaft, a flange mounted on said shaft to revolve therewith, a cooperating flange loosely sleeved upon said shaft and geared to the load, means whereby when one of said flanges is rotated relatively to the other said flanges are forced apart or separated, means operated by the separation of said flanges for frictionally coupling the same to revolve in unison, a friction-band connected to a part of said frictional coupling, a stationary bracket, a pawl pivotally mounted thereon and arranged to be engaged by said friction-strap, and a ratchet-ring connected to said part of the frictional coupling and with which said pawl cooperates, as and for the purpose set forth.

11. In a load-brake mechanism, a rotatable shaft, a flange mounted thereon to rotate therewith,a cooperating flange loosely sleeved upon said shaft and geared to the load, said flanges provided with interlocking spiral camsurfaces upon the opposed faces thereof and having bearing-surfaces upon the outer faces thereof, a casing with which said bearing-surfaces cooperate, said casing provided with a hub, a friction-strap mounted upon said hub, a pivotally-mounted pawl arranged to be engaged by said strap, and a ratchet connected to said casing and with which said pawl cooperates, as and for the purpose set forth.

12. In a load-brake mechanism, a rotatable shaft, a flange mounted thereon to rotate therewith,a cooperating flangelooselysleeved upon said shaft and geared to the load, said flanges provided with interlocking spiral camsurfaces upon the opposed faces thereof and having frictional bearing-surfaces, an inclosing casing with which said frictional bearingsurfaces respectively cooperate, said casing provided with a hub, friction-bands mounted upon said hub, locking-pawls arranged to be engaged by said friction-bands, and a ratchetring formed on said casing with which said locking-pawls cooperate, as and for the purpose set forth.

13. In a load-brakemechanism, a rotatable shaft, a flange mounted thereon to rotate therewith,a cooperating flangeloosely sleeved upon said shaftand geared to the load, a casing having frictional bearing-su rfaces respectively arranged to be engaged by cooperating frictional bearing-surfaces formed on said flanges to couple said flanges to revolve in unison, means whereby when one of said flanges is revolved relatively to the other said frictional engaging surfaces are brought into contact with each other, a hub formed on said casing, a ratchet-ring also formed on said casing, a fixed bracket, locking-pawls pivotally mounted thereon and provided with arms, friction-bands mounted upon said hub and arranged to engage said arms, said pawls cooperating with said ratchet-ring and stops for said pawls, as and for the purpose set forth.

In witness whereof I have hereunto set my hand, this 19th day of March, 1902, in the presence of the subscribing witnesses.

HARRY SAWYER.

\Vitnesses:

CHAS. H. SEEM, S. E. DARBY. 

